Defending the Assurance View of Testimonial Justification

What makes you justified in believing what people say or tell you? Until recently, theorists agreed that the answer to this question, whatever it is, does not in principle depend on whether you are addressed by the speaker or you merely overhear her tell something to someone else. The Assurance View of testimonial justification challenges that consensus. According to the Assurance View, in common situations of testimony you gain a distinct form of justification, the assurance justification, that derives from a distinct interaction, the assurance interaction, which requires a distinct form of trust, assurance trust, appropriate only to addressees. In this dissertation I defend the Assurance View by proposing a new version of it based on the idea that assurance trust detects for the speaker’s sincerity in the assurance interaction. This Detection View, I argue, can overcome the main objections to the Assurance View without departing, as some versions do, from assumptions about epistemic justification embraced in mainstream epistemology.